A high percentage of children in the primary stage of Spanish education perform as an extracurricular activity the practice of one or more sports to increase the weekly hours of physical activity. This together with eating habits give us a clear picture of how Spanish society is changing in relation to children's health. The main goal of this study is to relate the self-concept, the nutritional habits, the body image and the numbers of hours that children who already play football spend doing physical activity per week. The number of children that took part in this study was a sample of 124 schoolchildren in between 8 and 13 years old, of the Principality of Asturias. The surveys done for this study were Youth Physical Self-Concept Scale (C-PSQ), Multidimensional Body Self Relations Questionnaire (MBSRQ), Test Evaluation Preferences, Intentions of Conduct and Food Consumption (TEPICA) and Collins Silhouettes. Descriptives statistics were done, T-student tests for related and independent samples, variance analysis and Pearson correlation. The results showed that children who have good knowledge of nutricional habits correlates positively with the self-concept level. The results also show that the number of hours doing sports correlates positively with the perceived competency and self- concept. Also those children that aparently are satisfy with their bodies would like to be thiner.